Advances in solid state technology are continuously reducing the size of various electronic devices including computers and calculators. However, the size to which such device can be reduced has heretofore been limited by the size of the output display generally required in order to properly utilize such devices. Most miniature computers and related devices currently use as an output display a single row containing a limited number of matrices adapted for display of alphanumeric characters, such matrices being made up of light-emitting diodes, liquid crystals, or similar elements. Alternatively, where a full-page display is required, relatively large liquid crystal or similar flat-screen devices have been employed.
The former displays provide very little information, have low resolution, are not adapted for displaying graphics, and, particularly if liquid crystal elements are utilized, are difficult to view in low ambient light conditions. The devices are also not adapted for mounting so that the viewer may view the display without interrupting the user's normal vision.
The larger full-page flat-screen displays generally do not have particularly high resolution, still permit the viewing of only a limited amount of information, and are frequently difficult to view in low ambient light conditions. In addition, while smaller than a standard CRT monitor, these devices are still relatively bulky to carry or use. They are thus adapted for use with lap-top machines rather than pocket devices.
In some special applications, devices such as small headgear-mounted CRTs project an image through a suitable optical system to the user's field of vision. Such devices, sometimes referred to as heads-up displays, are relatively expensive and cumbersome and are therefore not adapted for general commercial use.
A need therefore exists for a miniature (i.e. pocket-sized) display which creates an apparent image of a full-sized, full-page video display, is relatively low cost, provides high resolution and can be viewed in any ambient light condition. Additionally, such a display can be adapted for viewing by no more than one eye so that the display can be viewed while at the same time maintaining normal vision.
A display of this type might be used whenever it was necessary to display full page of information with a pocket device. It could for example be utilized either as a miniature output device for a pocket-sized computer or as an output device from a modem for information provided from a central computer. It could also be utilized as a special purpose display in such applications as displaying information provided from a paging service, displaying stock market information to a broker or investor, either continuously such as a ticker tape, or selected information in response to a query, providing product and price information in the field to a salesman, providing output for a hand-held instrument such as an oscilloscope and the like. A miniaturized display of this type could also be mounted to glasses, a headband, or the like and used to provide data to pilots, tank operators, surgeons and others who require large amounts of alphanumeric or graphic information to perform a particular function while still being able to maintain substantially normal viewing. A related capability would be to provide a picture-phone capability with mobile telephones. A miniaturized display of this type would also be useful in applications where the user wishes to be able to view information without disturbing other people or having other people be able to see the information which is being viewed. A display device of this type would thus be useful in applications where the user wished to view a full-page display on an airplane or commuter train, at a library or at other public places where it is desirable that the display not be visible or distracting to others. Another application of a device of this type would be as a TV monitor which would be smaller and lighter than existing miniature TVs while providing a much larger effective screen, better resolution and easier viewing. Two such devices mounted to glasses or goggles to cover the user's full field of view could provide 3-D images useful for low-cost flight simulators or other applications.